MOBILE PHONE HACKED?

FACT. My wife & I were having lunch in a pub near Edinburgh when a call was made from my 'phone.
On checking my bank account my mobile phone bill was much higher than normal. On checking it I found a 3.33 second call at a cost of £16.680 had been made to a number starting 87076**. NO ZERO at start.
On checking WHITE NUMBERS this was shown as a landline number in DYESS Arkansas near a American Air Force base! The 'phone company said it is a ship?
I contacted my mobile phone company who were not helpful but they will be sorted!!!!
Question, Is it possible for my mobile phone to be hacked into when it was in my possession at the time of the call being made?